diff --git a/floris/simulation/farm.py b/floris/simulation/farm.py
index 8bab263f1..1524e75e5 100644
--- a/floris/simulation/farm.py
+++ b/floris/simulation/farm.py
@@ -184,6 +184,10 @@ def __attrs_post_init__(self) -> None:
         if len(_turbine_types) == 1:
             _turbine_types *= self.n_turbines
 
+        # Check that turbine definitions contain any v3 keys
+        for t in _turbine_types:
+            check_turbine_definition_for_v3_keys(turbine_definition_cache[t])
+
         # Map each turbine definition to its index in this list
         self.turbine_definitions = [
             copy.deepcopy(turbine_definition_cache[t]) for t in _turbine_types
@@ -404,3 +408,38 @@ def coordinates(self):
     @property
     def n_turbines(self):
         return len(self.layout_x)
+
+def check_turbine_definition_for_v3_keys(turbine_definition: dict):
+    """Check that the turbine definition does not contain any v3 keys."""
+    v3_deprecation_msg = (
+        "Consider using the convert_turbine_v3_to_v4.py utility in floris/tools "
+        + "to convert from a FLORIS v3 turbine definition to FLORIS v4. "
+        + "See https://nrel.github.io/floris/upgrade_guides/v3_to_v4.html for more information."
+    )
+    if "generator_efficiency" in turbine_definition:
+        raise ValueError(
+            "generator_efficiency is no longer supported as power is specified in absolute terms "
+            + "in FLORIS v4. "
+            + v3_deprecation_msg
+        )
+
+    v3_renamed_keys = ["pP", "pT", "ref_density_cp_ct", "ref_tilt_cp_ct"]
+    if any(k in turbine_definition for k in v3_renamed_keys):
+        v3_list_keys = ", ".join(map(str,v3_renamed_keys[:-1]))+", and "+v3_renamed_keys[-1]
+        v4_versions = (
+            "cosine_loss_exponent_yaw, cosine_loss_exponent_tilt, ref_air_density, and ref_tilt"
+        )
+        raise ValueError(
+            v3_list_keys
+            + " have been renamed to "
+            + v4_versions
+            + ", respectively, and placed under the power_thrust_table field in FLORIS v4. "
+            + v3_deprecation_msg
+        )
+
+    if "thrust" in turbine_definition["power_thrust_table"]:
+        raise ValueError(
+            "thrust has been renamed thrust_coefficient in FLORIS v4 (and power is now specified "
+            "in absolute terms with units kW, rather than as a coefficient). "
+            + v3_deprecation_msg
+        )
diff --git a/floris/simulation/floris.py b/floris/simulation/floris.py
index 2f04b4a13..a71377a60 100644
--- a/floris/simulation/floris.py
+++ b/floris/simulation/floris.py
@@ -347,6 +347,7 @@ def from_file(cls, input_file_path: str | Path) -> Floris:
             Floris: The class object instance.
         """
         input_dict = load_yaml(Path(input_file_path).resolve())
+        check_input_file_for_v3_keys(input_dict)
         return Floris.from_dict(input_dict)
 
     def to_file(self, output_file_path: str) -> None:
@@ -362,3 +363,36 @@ def to_file(self, output_file_path: str) -> None:
                 sort_keys=False,
                 default_flow_style=False
             )
+
+def check_input_file_for_v3_keys(input_dict) -> None:
+    """
+    Checks if any FLORIS v3 keys are present in the input file and raises special errors if
+    the extra keys belong to a v3 definition of the input_dct.
+    and raises special errors if the extra arguments belong to a v3 definition of the class.
+
+    Args:
+        input_dict (dict): The input dictionary to be checked for v3 keys.
+    """
+    v3_deprecation_msg = (
+        "Consider using the convert_floris_input_v3_to_v4.py utility in floris/tools "
+        + "to convert from a FLORIS v3 input file to FLORIS v4. "
+        "See https://nrel.github.io/floris/upgrade_guides/v3_to_v4.html for more information."
+    )
+    if "turbulence_intensity" in input_dict["flow_field"]:
+        raise AttributeError(
+            "turbulence_intensity has been updated to turbulence_intensities in FLORIS v4. "
+            + v3_deprecation_msg
+        )
+    elif not hasattr(input_dict["flow_field"]["turbulence_intensities"], "__len__"):
+        raise AttributeError(
+            "turbulence_intensities must be a list of floats in FLORIS v4. "
+            + v3_deprecation_msg
+        )
+
+    if input_dict["wake"]["model_strings"]["velocity_model"] == "multidim_cp_ct":
+        raise AttributeError(
+            "Dedicated 'multidim_cp_ct' velocity model has been removed in FLORIS v4 in favor of "
+            + "supporting all available wake models. To recover previous operation, set "
+            + "velocity_model to gauss. "
+            + v3_deprecation_msg
+        )
diff --git a/floris/tools/convert_floris_input_v3_to_v4.py b/floris/tools/convert_floris_input_v3_to_v4.py
new file mode 100644
index 000000000..36415e1d2
--- /dev/null
+++ b/floris/tools/convert_floris_input_v3_to_v4.py
@@ -0,0 +1,70 @@
+
+import sys
+from pathlib import Path
+
+import yaml
+
+from floris.utilities import load_yaml
+
+
+"""
+This script is intended to be called with an argument and converts a floris input
+yaml file specified for FLORIS v3 to one specified for FLORIS v4.
+
+Usage:
+python convert_floris_input_v3_to_v4.py <path/to/floris_input>.yaml
+
+The resulting floris input file is placed in the same directory as the original yaml,
+and is appended _v4.
+"""
+
+
+if __name__ == "__main__":
+    if len(sys.argv) != 2:
+        raise Exception(
+            "Usage: python convert_floris_input_v3_to_v4.py <path/to/floris_input>.yaml"
+        )
+
+    input_yaml = sys.argv[1]
+
+    # Handling the path and new filename
+    input_path = Path(input_yaml)
+    split_input = input_path.parts
+    [filename_v3, extension] = split_input[-1].split(".")
+    filename_v4 = filename_v3 + "_v4"
+    split_output = list(split_input[:-1]) + [filename_v4+"."+extension]
+    output_path = Path(*split_output)
+
+    # Load existing v3 model
+    v3_floris_input_dict = load_yaml(input_yaml)
+    v4_floris_input_dict = v3_floris_input_dict.copy()
+
+    # Change turbulence_intensity field to turbulence_intensities as list
+    if "turbulence_intensities" in v3_floris_input_dict["flow_field"]:
+        if "turbulence_intensity" in v3_floris_input_dict["flow_field"]:
+            del v4_floris_input_dict["flow_field"]["turbulence_intensity"]
+    elif "turbulence_intensity" in v3_floris_input_dict["flow_field"]:
+        v4_floris_input_dict["flow_field"]["turbulence_intensities"] = (
+            [v3_floris_input_dict["flow_field"]["turbulence_intensity"]]
+        )
+        del v4_floris_input_dict["flow_field"]["turbulence_intensity"]
+
+    # Change multidim_cp_ct velocity model to gauss
+    if v3_floris_input_dict["wake"]["model_strings"]["velocity_model"] == "multidim_cp_ct":
+        print(
+            "multidim_cp_ct velocity model specified. Changing to gauss, "
+            + "but note that other velocity models are also compatible with multidimensional "
+            + "turbines in FLORIS v4. "
+            + "You will also need to convert your multidimensional turbine yaml files and their "
+            + "corresponding power/thrust csv files to be compatible with FLORIS v4 and to reflect "
+            + " the absolute power curve, rather than the power coefficient curve."
+        )
+        v4_floris_input_dict["wake"]["model_strings"]["velocity_model"] = "gauss"
+
+    yaml.dump(
+            v4_floris_input_dict,
+            open(output_path, "w"),
+            sort_keys=False
+        )
+
+    print(output_path, "created.")
diff --git a/floris/tools/convert_turbine_v3_to_v4.py b/floris/tools/convert_turbine_v3_to_v4.py
index 7e5b9e123..5cf55f3d5 100644
--- a/floris/tools/convert_turbine_v3_to_v4.py
+++ b/floris/tools/convert_turbine_v3_to_v4.py
@@ -11,7 +11,7 @@
 yaml file specified for FLORIS v3 to one specified for FLORIS v4.
 
 Usage:
-python convert_turbine_yaml_v3_to_v4.py <path/to/turbine>.yaml
+python convert_turbine_v3_to_v4.py <path/to/turbine>.yaml
 
 The resulting turbine is placed in the same directory as the original yaml,
 and is appended _v4.
@@ -20,7 +20,7 @@
 
 if __name__ == "__main__":
     if len(sys.argv) != 2:
-        raise Exception("Usage: python convert_turbine_yaml_v3_to_v4.py <path/to/turbine>.yaml")
+        raise Exception("Usage: python convert_turbine_v3_to_v4.py <path/to/turbine>.yaml")
 
     input_yaml = sys.argv[1]
 
@@ -37,6 +37,13 @@
 
     # Split into components expected by build_turbine_dict
     power_thrust_table = v3_turbine_dict["power_thrust_table"]
+    if "power_thrust_data_file" in power_thrust_table:
+        raise ValueError(
+            "Cannot convert multidimensional turbine model. Please manually update your "
+            + "turbine yaml. Note that the power_thrust_data_file csv needs to be updated to "
+            + "reflect the absolute power curve, rather than the power coefficient curve,"
+            + "and that `thrust` has been replaced by `thrust_coefficient`."
+        )
     power_thrust_table["power_coefficient"] = power_thrust_table["power"]
     power_thrust_table["thrust_coefficient"] = power_thrust_table["thrust"]
     power_thrust_table.pop("power")
diff --git a/tests/data/nrel_5MW_custom.yaml b/tests/data/nrel_5MW_custom.yaml
index 9e3ef6735..b7d3d8e5b 100644
--- a/tests/data/nrel_5MW_custom.yaml
+++ b/tests/data/nrel_5MW_custom.yaml
@@ -1,166 +1,174 @@
 turbine_type: 'nrel_5MW_custom'
-generator_efficiency: 1.0
 hub_height: 90.0
-pP: 1.88
-pT: 1.88
 rotor_diameter: 126.0
 TSR: 8.0
-ref_density_cp_ct: 1.225
-ref_tilt_cp_ct: 5.0
 power_thrust_table:
+  cosine_loss_exponent_yaw: 1.88
+  cosine_loss_exponent_tilt: 1.88
+  ref_air_density: 1.225
+  ref_tilt: 5.0
   power:
     - 0.0
-    - 0.000000
-    - 0.000000
-    - 0.178085
-    - 0.289075
-    - 0.349022
-    - 0.384728
-    - 0.406059
-    - 0.420228
-    - 0.428823
-    - 0.433873
-    - 0.436223
-    - 0.436845
-    - 0.436575
-    - 0.436511
-    - 0.436561
-    - 0.436517
-    - 0.435903
-    - 0.434673
-    - 0.433230
-    - 0.430466
-    - 0.378869
-    - 0.335199
-    - 0.297991
-    - 0.266092
-    - 0.238588
-    - 0.214748
-    - 0.193981
-    - 0.175808
-    - 0.159835
-    - 0.145741
-    - 0.133256
-    - 0.122157
-    - 0.112257
-    - 0.103399
-    - 0.095449
-    - 0.088294
-    - 0.081836
-    - 0.075993
-    - 0.070692
-    - 0.065875
-    - 0.061484
-    - 0.057476
-    - 0.053809
-    - 0.050447
-    - 0.047358
-    - 0.044518
-    - 0.041900
-    - 0.039483
     - 0.0
+    - 40.518011517569214
+    - 177.67162506419703
+    - 403.900880943964
+    - 737.5889584824021
+    - 1187.1774030611875
+    - 1239.245945375778
+    - 1292.5184293723503
+    - 1347.3213147477102
+    - 1403.2573725578948
+    - 1460.7011898730707
+    - 1519.6419125979983
+    - 1580.174365096404
+    - 1642.1103166918167
+    - 1705.758292831
+    - 1771.1659528893977
+    - 2518.553107505315
+    - 3448.381605840943
+    - 3552.140809000129
+    - 3657.9545431794127
+    - 3765.121299313842
+    - 3873.928844315059
+    - 3984.4800226955504
+    - 4096.582833096852
+    - 4210.721306623712
+    - 4326.154305853405
+    - 4443.395565353604
+    - 4562.497934188341
+    - 4683.419890251577
+    - 4806.164748311019
+    - 4929.931918769215
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
+    - 5000.00
     - 0.0
-  thrust:
     - 0.0
+  thrust_coefficient:
     - 0.0
     - 0.0
-    - 0.99
-    - 0.99
-    - 0.97373036
-    - 0.92826162
-    - 0.89210543
-    - 0.86100905
-    - 0.835423
-    - 0.81237673
-    - 0.79225789
-    - 0.77584769
-    - 0.7629228
-    - 0.76156073
-    - 0.76261984
-    - 0.76169723
-    - 0.75232027
-    - 0.74026851
-    - 0.72987175
-    - 0.70701647
-    - 0.54054532
-    - 0.45509459
-    - 0.39343381
-    - 0.34250785
-    - 0.30487242
-    - 0.27164979
-    - 0.24361964
-    - 0.21973831
-    - 0.19918151
-    - 0.18131868
-    - 0.16537679
-    - 0.15103727
-    - 0.13998636
-    - 0.1289037
-    - 0.11970413
-    - 0.11087113
-    - 0.10339901
-    - 0.09617888
-    - 0.09009926
-    - 0.08395078
-    - 0.0791188
-    - 0.07448356
-    - 0.07050731
-    - 0.06684119
-    - 0.06345518
-    - 0.06032267
-    - 0.05741999
-    - 0.05472609
+    - 1.132034888
+    - 0.999470963
+    - 0.917697381
+    - 0.860849503
+    - 0.815371198
+    - 0.811614904
+    - 0.807939328
+    - 0.80443352
+    - 0.800993851
+    - 0.79768116
+    - 0.794529244
+    - 0.791495834
+    - 0.788560434
+    - 0.787217182
+    - 0.787127977
+    - 0.785839257
+    - 0.783812219
+    - 0.783568108
+    - 0.783328285
+    - 0.781194418
+    - 0.777292539
+    - 0.773464375
+    - 0.769690236
+    - 0.766001924
+    - 0.762348072
+    - 0.758760824
+    - 0.755242872
+    - 0.751792927
+    - 0.748434131
+    - 0.745113997
+    - 0.717806682
+    - 0.672204789
+    - 0.63831272
+    - 0.610176496
+    - 0.585456847
+    - 0.563222111
+    - 0.542912273
+    - 0.399312061
+    - 0.310517829
+    - 0.248633226
+    - 0.203543725
+    - 0.169616419
+    - 0.143478955
+    - 0.122938861
+    - 0.106515296
+    - 0.093026095
+    - 0.081648606
+    - 0.072197368
+    - 0.064388275
+    - 0.057782745
     - 0.0
     - 0.0
   wind_speed:
     - 0.0
-    - 2.0
-    - 2.5
+    - 2.9
     - 3.0
-    - 3.5
     - 4.0
-    - 4.5
     - 5.0
-    - 5.5
     - 6.0
-    - 6.5
     - 7.0
+    - 7.1
+    - 7.2
+    - 7.3
+    - 7.4
     - 7.5
+    - 7.6
+    - 7.7
+    - 7.8
+    - 7.9
     - 8.0
-    - 8.5
     - 9.0
-    - 9.5
     - 10.0
+    - 10.1
+    - 10.2
+    - 10.3
+    - 10.4
     - 10.5
+    - 10.6
+    - 10.7
+    - 10.8
+    - 10.9
     - 11.0
+    - 11.1
+    - 11.2
+    - 11.3
+    - 11.4
     - 11.5
+    - 11.6
+    - 11.7
+    - 11.8
+    - 11.9
     - 12.0
-    - 12.5
     - 13.0
-    - 13.5
     - 14.0
-    - 14.5
     - 15.0
-    - 15.5
     - 16.0
-    - 16.5
     - 17.0
-    - 17.5
     - 18.0
-    - 18.5
     - 19.0
-    - 19.5
     - 20.0
-    - 20.5
     - 21.0
-    - 21.5
     - 22.0
-    - 22.5
     - 23.0
-    - 23.5
     - 24.0
-    - 24.5
     - 25.0
-    - 25.01
-    - 25.02
+    - 25.1
     - 50.0